In this paper, a number of ¹³C NMR Spectra data of flavonoid compounds were studied and analysed. The characteristics of ¹³C NMR spectra and the rules of chemical shifts in the backbone of different flavonoid compounds were obtained. The factors affecting the chemical shifts of flavonoid compounds were discussed and the knowledge database for computer-aided ¹³C NMR spectra elucidation of flavonoid natural products was established.

In this paper, a theoretical analysis on DANTE experiments in rotating solids is presented. In chemical shift interaction frame, the motional equation of the spin systems has been solved under the zeroth-order approximation by applying the average Hamiltonian theory. As a result, the selectivity of the DANTE sequence has been discussed. Finally, a related experimental result is shown.

The properties of Mn²⁺ ions and the signal of the defect used in dating for natural calcite were analysed by ESR. Theoretical calculation agrees satisfactorily with experimental results on ESR spectra. Experimental phenomena in the heat treatment and the irradiation of the sample were explained. A method is proposed to overcome the interference from impurities of Mn²⁺ ions in the sample.

Complete ¹H and ¹³C chemical shifts assignments of three kinds of b-dihydroagarofuran sesquiterpcnoids (1-3) were carried out on the basis of ¹H, ¹³C-COSY and ¹H, ¹³C long-range COSY(COLOC) spectra. An exact examination and comparison of the relationship between the ¹³C chemical shifts for C-14 and the stereochemistry at C-8 and C-9 for these compounds, as well as nineteen other various β-dihydroagarofuran compounds, have led to a new and very important means of conformational characterization.

A method of determining the three-dimensional structure for proteins in aqueous solution by a set of distance constraints between backbond atoms (mainly for H-H, obtained from NMR) was developed. In this method, only dihedral angles were selected as independent variables, a proper target function was minimized by local-to-globular optimization, thus these dihedral angles and the coordinates of six kinds of the backbond atoms (N, H^N, C^α, H^α, C', O) were calculated. The program DISNMA for this method was designed, and proved with the standad structure of BPTI. It requires less amount of memory space and computing time and can be used for other larger molecules.

A synchronous controlling equipment is described in this paper. 2D flipping angle correlation spectra of singre crystal have been obtained on MSL-400 NMR speoerorneter using this flipping angle device. ¹³C chemical shift tensors in typical crystal DGO (2NH₃⁺CH₂COO^-·2·COOH) are presented.

We have investigated the properties of electron paramagnetic resonance (EPR) spectra from undoped-, FeCl₃-and iodine-doped poly (paraphenylene) (PPP) prepared by the method of Kovacic. EPR measurements were used to characterize electronic states relevant for polaron transformation in doped PPP. it was found that a novel phenomenon of ihe dependence of room temperature linewidth(△H_pp) and spin concentration (N_spin) on the dopant concentrations for iodine-doped PPP, namely, △H_pp first decreased and increased; and then decreased and increased again with increasing of iodine concentrations in the iodine-doped PPP, Correspondingly, N_spin first increased and decreased; and then increased and decreased again with increasing of iodine concentration in PPP. However, the changes of △H_pp and N_spin in FeCl₃-doped PPP are not similar to those in the iodine-doped PPP system. We explained this difference、Due to the interaction between spins on the polymer chains and dopant molecule, the observed g-factor values are close to the free electron value and do not substantially vary with the kind of dopant and temperature.

The variation of ESR parameters, such as g factor, line-shape factor (l), peak to peak linewidth (ΔB_pp) and spin density (Ns), with the composition (x) for electron beam evaporated a-Si_1-xNd_x films was studied. Based on the optical absorption and conductive properties in this kind of alloy films, using the dangling bond model with Nd back bonds, the variation of properties are analyzed and discussed.

In this paper the ¹³C NMR spectra of polyacrylate triphenyl-phosphonium chloride have been studied. The relationship between the structure of macromolecule phosphonium salts and carbon-phosphonium coupling constants was discussed. By the method of inverse gate decoupling of ¹³C NMR spectra, molecular weight of polyacrylate triphenylphosphonium chloride and block ratio of block polyacrylate triphenylphosphonium chloride were determined.

The ¹H NMR spectra have been determined for eleven Mo(W)-Cu-S metal cluster compounds containing dialkyldithiocarbamate ligands R₂NCS₂ (R₂=Me₂,Et₂, C₄H₈, C₅H₁₀) at room temperature. The linewidth of α-H (methylene or methyl protons)of the ligands are broadened seriously, because these compounds are heteronuclear. The relation between the shifts of α-H, the structure of the compounds and the average of Cu-S bond lengths is discussed also.

The carbon-13 nuclear magnetic resonance spectra of seventeen sesquiterpenoid aromatic esters possessing protoilludane skeleton have been analysed and assigned. The information should be useful for the structure elucidation of new protoilludane sesquiterpenoid aromatic esters.

The molecular configuration of new synthesized five pairs of title compounds were confirmed by using ¹H NMR, NOE difference spectra and gated decoupling ¹³C NMR etc..The NMR spectra were assigned by means of PRFT, APT ¹³C NMR, 2D C-H COSY spectra and ¹³C-¹⁹F coupling constants.

Starting from the operational characteristics of gas laser, we have derived the mathematical descriptions of the first derivative signals of intracavity laser magnetic resonance absorption and its Doppler-free saturation absorption. The relations between LMR signal and the sample pressure, laser light intensity have been investigated experimentally. A detailed discussion about the characteristics of Doppler-free saturation absorption of NO in intracavity laser magnetic resonance is presented in this paper.

A new method of designing MQ excitation pulse-sequences with high efficiency and coherences of the highest order P_max=N, where N is the total spin number, is proposed. According to the different spin coupling networks, the pulse sequences were designed by the bilinear rotation pulses as basic excitation elements. The relations between the pulse sequences and the spin coupling networks were established and can be applied to the simplification of complex spectra and confirmation of coupling networks.

Two new compounds were isolated from the roots of Zanthoxylum schinifolium Sieb. et Zucc. The structures were determined by 1D and 2D NMR techniques. They were named as Schinifolin and Acetoxyschinifolin, respectively.